Your letters

By Reader's letters

Published Monday, August 11, 2014

Send your letters to The Editor, E&T, Michael Faraday House, Six Hills Way, Stevenage, Herts SG1 2AY, UK, or to engtechletters@theiet.org. We reserve the right to edit letters and to use submissions in any other format.

Smart meters – game changer or white elephant?

Recent letters in E&T have argued that the smart-metering system in Great Britain is too complicated and other countries have a sounder approach. I do not agree. The Department of Energy and Climate Change views smart meters as a game changer for consumers and for energy retailing, as well as providing the foundations for the smart grid.

Our strategy is to maximise the benefits they offer, which we estimate to be £6.2bn above their total cost. These benefits include not just the direct potential for consumers to save energy, but also the straightforward reduction in the cost of operating our metering and billing infrastructure, plus a chance for DNOs and other users to see this as a new toolkit to help them implement the smart grid and smart energy solutions.

We are tackling gas as well as electricity. Beyond accurate automatic billing, reduced industry costs and faster switching, we require in-home displays to empower consumers; pre-payment functionality on all meters; time-of-use tariffs; load control and appliance automation; as well as robust privacy controls and encryption.

The specifications have been defined in partnership with industry and government experts. This has included consulting with IET members and the engineering profession more widely in their development, and DECC has greatly valued the constructive challenge and input from IET experts. Smart metering will give consumers the information and tools they need to take control of their energy usage leading to reduced consumption, industry costs, carbon emissions and bills.

The real elephant in the room regarding smart meters is the ability to remotely disconnect customers. Ostensibly this facility is to limit the debt run up by individual defaulting customers, but it takes a very small stretch of imagination to see how it could be used for widespread load shedding, which will probably be necessary as a result of the long-term underinvestment in nuclear power.

There is much propaganda surrounding the roll-out, which is designed to convince naive or ill-informed customers that they will be beneficial. An outstanding example is the British Gas advert, which suggests that a smart meter will enable one to determine the consumption of a phone charger.

JR Ball MIETHale

Buy books and we’ll stock them

I read with interest Allen Brown’s letter in the June 2014 issue of E&T about the lack of books on electronics, electrical engineering and telecommunications at our shop. Sadly, I can only agree with his analysis of the section. In fact, the only thing more depressing than the number of titles on the shelf is the level of sales the section now produces. Over recent years, sales of books in this area have declined rapidly, as they have in the nearby computing section.

Believe me, selling books is my business, so if I could sell more I would stock more. Sales in the other areas Allen mentions haven’t suffered the same fate – which is why the range is still significant in those sections.

We’re always keen to learn and improve, though. So, if Allen would like to get in touch I’d be happy to discuss what else we can do and how we can attract all those Cambridge engineers into the bookshop. In fact, if any of your readers want to recommend great titles in this area I’d be happy to give them a try.

David RobinsonManager, Heffers, 20 Trinity Street, Cambridge

Where’s the will for wave power?

While LJ White is correct about how ‘slack water’ affects output from tidal and wave power installations, there will always be at least four places in the sea around Britain where the flow is sufficient for good power generation. What we need is the will to make it happen.

In 2011 a leading Swedish company in the field regarded the work at Oxford University on a transverse horizontal axis water turbine as potential major competition. Unfortunately since then it seems to be lacking support to make real progress. The government seems fixated on wind.

If the proposed tidal lagoons you’ve written about recently are built, the THAWT might be a suitable power generator. The lagoon walls could benefit from the Paul Brinklow’s suggestion (Letters, August) of using landfill in mash concrete to reduce cost.

While the tidal lagoons are only suggested for the west coast, it should be noted that two high and two low tides circulate around Britain’s coast at all times. Adding lagoons on the east coast at suitable locations would ensure that power generation could be continuous.

Alfred Reading MIETSurrey

Real challenge for smarter heating

All the clever devices described in your article about smart thermostats and heating controls (E&T, August 2014) are going to have to be interfaced with existing boilers, circulating pumps and two- and three-way valves in order to work their magic – and that’s the hard part.

Has anyone stopped to consider the overall response of a typical domestic house and heating system with, maybe, a 15-year-old boiler with no remote temperature control, just a knob on the front, in one room; a couple of control valves and a circulating pump about the same age in the bathroom or the cupboard under the stairs or the airing cupboard, and an existing thermostat which is likely to be in the hall, or in the living room, or some other place where the majority of the family aren’t?

How will the magic new thermostats achieve worthwhile savings when connected to that lot – and who is going to make the connections? Industrial systems are very different and have had outside and inside compensation, multiple heating circuits, variable speed pumps and the like for years.

The average domestic system is inadequately specified and totally unsuitable for the connection of modern controls. That’s the challenge, not making cleverer thermostats.

J M Butcher, MIETBy email

Let’s shout about CEng

I think it is unlikely that we can retrieve the word engineer from the general English usage into which it has evolved. It certainly does our case no good by trying to demote thousands of craftsmen and technicians in order to enhance our own position, especially as the problem is not of their making. They are referred to as engineers by their employers for commercial reasons.

It may be helpful to look at other professions. Medical doctors have done well by annexing a prestigious academic rank, but I wonder why their upper ranks insist on being called Mr.Clerks, bookkeepers and cashiers all call themselves accountants. The professionals in that sector do not seem to worry about it but they jealously guard the use of the letters CA. They take legal action for the misuse of the title and discipline members who misbehave. When their children ask “what do you do,” they reply, “I’m a chartered accountant”. Their children run off to school and boast about it.

Status is of course not something that can be taken. It is decided by society in general. I agree that it is sad that we can no longer describe ourselves simply as engineers. The first step is to make sure society understands that chartered engineers exist. To this end we must use our title on all possible occasions, when signing appropriate documents, when dealing with the media and most importantly when our children and others ask what we do. I seldom see CEng in documents or in the media. We can put that right.

Phil Holbrook CEng FIETCardiff

How Britain got its plug design

Michael Bacon (Letters, August) draws attention to the dangers arising from a 13A plug left on the floor with the pins up, a hazard that does not arise from the in-line plugs used elsewhere in the world.

The origin of this lies with the requirement in the 3rd or 4th edition of the Wiring Regulations, which forbade the use of in-line plugs. I have not searched for the reason, but I think that it was because an in-line plug is more easily accidentally pulled out of the socket. At the time, DC was still widely in use and pulling a plug out carrying 15A (or even 5A) would be extremely exciting.

When BSI was instructed by the Post-War Reconstruction Committee to produce a standard for a fused 13A plug, being set in their ways, the manufacturers probably did not consider an in-line plug. What is known is that Dorman and Smith were asked whether their plug with the fuse in the live pin could be adopted as the standard; they refused, to their later regret, and BSI adopted the design that we now have. It seems, anecdotally, to have been the plug produced by MK and shown to the committee in 1944.

It might have been possible to produce an in-line plug with a renewable fuse such as we have now; it would still be the bulky thing that we have now. What is certain is that an in-line plug using a Dorman and Smith type screw-in fuse pin could readily be produced and French and German plugs could be readily adopted, were they mad enough to adopt the 30A ring circuit (though it is questionable as to whether a fuse is needed in a circuit protected by a 30A mcb). The Germans did, for a short while, consider the possibility of adopting the ring circuit but were advised not to.

If we ever get a Europlug, without a fuse, 2.5mm2 radials, protected by a 20A mcb, each feeding 50M2 – which is what the IET now advise – will be quite safe.

Do you need a password manager?

The focus on password managers in your July issue (Software Reviews) is misleading because it leaves the impression that they are a good thing. They are not really required.

The trouble with a password manager is it is a single point of failure. Something us engineers try to avoid. If your master password is known all the other passwords are opened up. Is that good security? Us humans are usually the weakest link in the security chain. If your password file is stored on a mobile or laptop and that device is lost or stolen you’ll have that nagging ill feeling it may get into the wrong hands and you’ll want to change all those passwords stored in the manager. What a chore.

As an experienced software engineer my tips are: a password manager is not needed, it’s just another piece of software to manage; have two email addresses, one for public correspondence, one for logins; don’t generate passwords but long passphrases; have your own personal, repeatable algorithm for producing a passphrase; if possible don’t store credit or debit card details on a device, your physical card is additional security.

Daniel Fowler CEng MIETBy email

Being frugal with water

There was a time when I would have taken inspiration from Charles Leadbeater (Book Interview, July 2014) but after spending the last three years or so on a frugal engineering project I am full of cynicism.

Partly out of frustration owing to time spent watching several litres of water disappear down the plughole whenever I turned on a ‘hot’ water tap, due to it being cooled after resting in the ‘hot’ interconnecting lines, I invented a complete solution to the problem. Crucially, it saves significant amounts of water.

I accept that there are proven methods, such as the return loop through which hot water is continually circulated, instant flow heaters that can be installed in the cold supply line close to the user point, or a small storage-type water heater fitted close to the user point. All of these options have disadvantages and are often difficult to retrofit.

My method is to fit a small water-storage heater in the hot-water line, close to the user point, which provides instant hot water while automatically retaining cold water where it is heated in readiness for subsequent demands. Hot water bypasses the unit to go direct to the user point. I would challenge anyone to find anything like it on the market at the moment.

Frugally, I built several successful prototypes, in my shed, and have applied for a patent. For the most part I used/adapted readily-available components. Essentially, it is compatible with DIY applications.

So far, everyone I’ve approached thinks it is a good idea. However, I conclude that industry only pays lip service to the idea of water saving. I was told by one leading manufacturer of water heaters: “We are not in the business of saving water.” And from the water supply industry, I was politely given an audience but have not received any sort of endorsement which might have helped me in my approach to manufacturers. Government departments quickly sidestep the issue by suggesting I contact other departments.

Donald Webb CEng MIETColchester

Designing a better hearing aid

I wear a hearing aid from one of the major manufacturers and without it I’m badly deaf in terms of hearing speech, although I can still hear ‘low-information’ sound such as road traffic, doors shutting and so on. However, one area which I, and almost certainly all other hearing aid users, find particularly uncomfortable is the classic one of percussive noise. I have to turn the aid off completely, for example, when washing or handling dishes and cutlery.

Although the aid incorporates clipping of loud sound levels, this cannot be the answer as, by the time the clipping function operates, the signal has passed through the aid so that the ear hears the clipped level and has experienced the rapid rise wavefront.

I don’t know whether it’s high absolute signal level or steep wavefront that causes the discomfort, but I wonder whether they couldn’t both be eliminated by time-delaying all signals passing through the aid. It shouldn’t be impossible with the processing power of modern aids.

I would imagine that 2-3ms delay would not be noticed by the wearer of the aid, as it would be equivalent only to moving a speaker about 1m further away, but it would give the aid’s processor time to sense that a wavefront is rising more steeply than a typical speech wavefront, and/or note that such a wavefront has reached, or will reach, the clipping level.

What would or should then be done with these sounds? Can they simply be totally blocked, or would that produce odd hearing effects? Should the clipping level be greatly reduced? This might reduce some of the discomfort, but the steep wavefront rise probably needs to be totally blocked from passing through the aid.

Neil Muir MIETShrewsbury

Tanks in your high street

I was interested to read about the recovery of First World War tanks in ‘Relics of the Great War’ in July’s E&T. Visitors to Ashford in Kent may be surprised to find a First World War Mark IV on display in one of the busiest shopping streets, where it has stood for almost 100 years. The ‘female’ Mark IV, armed with six Lewis machine guns, was presented to the people of Ashford in 1919 by the Army Council, in recognition of their support of the National War Savings Appeals.

A number of other towns around the country also received tanks after the war as a monument of thanks. The majority of these, including the one which used to stand by Maidstone Bridge, were recovered for scrap metal during the Second World War. The main reason that Ashford’s tank survived was that in 1929 the mechanical workings were removed and an electricity substation was installed inside!

The substation has now been removed and the tank was completely renovated by the REME in 1978. It was formally registered as a war memorial on 11/11/2006.

Paul Atkinson MIETBy email

Transport highs and lows

In answer to Robert J Hayes' letter in the August issue of E&T,Britain's trolley-buses were discontinued because they could not economically cope with albeit temporary road closures and diversions, new building estates going up near existing routes etc.

But they were comfortable, one did not have to risk life and limb to get aboard them, and they were quiet.

WH Philpott CEng MIETBy email

Correcting an earlier claim that China’s Lanzhou-Urumqi railway is the highest in the world, you acknowledge that those in the Andes are higher. In fact the highest railway is the Qinghai-Tibet track which reaches 5,072m altitude. Not a high speed track, but still a marvel.